This program project grant will enable the New York State Department of Health, Cancer Control Bureau to carry through long range epidemiologic studies of cancer etiology. It provides for staff necessary to gather and analyze data and to facilitate research use of the State Cancer Registry and other records available to the Health Department. The Research Plan describes projects relating to several cancer sites. Colon cancer will be studied in Watertown, New York where the incidence is higher than other areas in New York State and among residents of State Mental Hospitals who have a low frequency of this disease. The hypothesis of transmissibility of Hodgkin's disease will be tested further and methods developed for extending these studies to other lymphatic and hematopoietic neoplasms. Additional studies are in progress or planned for cancers of the prostate, pancreas, breast, central nervous system, (primary) liver and mesothelium.